氯化钠对铝硅矿物浮选的影响及其作用机理

采用季铵盐DTAL作捕收剂,研究了氯化钠对一水硬铝石和叶蜡石浮选的影响及其作用机理.随着氯化钠浓度的增加,叶蜡石的浮选回收率显著提高,而一水硬铝石的可浮性受其影响很小.机理研究表明:氯化钠对一水硬铝石的zeta-电位没有影响,而能显著降低叶蜡石的zeta-电位,增强捕收剂与叶腊石的静电作用,促进捕收剂的吸附而活化其浮选;叶蜡石表面电位的降低是因为氯离子对叶蜡石存在选择性吸附作用并对其结构进行插层,使得叶蜡石的层间距从0.93 nm增大至1.40 nm.溶液化学计算表明:氯化钠改变溶液的离子强度,显著降低了季铵盐阳离子表面活性剂的临界胶束浓度,使得吸附了捕收剂的矿物表面更容易疏水上浮.     

Flotation of kaolinite and its interaction with hexadecylammonium bromide

1　INTRODUCTIONAshasbeenextensivelydiscussedinRef .[1],theselectiveseparationofbauxiteisextremelycom plexinseveralcases ,theproblemsinvolvedarenotyetfullyresolved .Thetechnologicalschemesofposi tive flotationorreverse flotationseparationofalu minum silicatemineralsfromdiasporicbauxiteweresuggested[2 ,3] .The positive flotationseparationofbauxiteisfinishedbydepressingaluminumsilicateganguemineralssuchasillite ,kaoliniteandpy rophillite,andusesanioniccollectorstofloatdias pore .Phosphate ,s…     

Effect of hydroxamic acid starch on reverse flotation desilicate from diasporic bauxite

It is important to depress diaspore effectively in order to remove silicates from diasporic bauxite.A new water soluble polymer hydroxamic acid starch(HA-starch)was prepared.The effects of the product on the diaspore and kaolinite flotation were investigated and its reactive mechanism was studied by zeta potential measurement and FTIR.The results show that HA-starch can depress diaspore while make positive effect on kaolinite flotation at low pH value(pH below 6)The flotation recovery of diaspore was sharply decreased with the increase of concentration of HA-starch.The chemical adsorption of HA-starch on the surface of diaspore was revealed.     

硬质和软质高岭石的晶体结构与浮选行为

研究了硬质与软质高岭土中的高岭石晶体结构、晶体形态与表面性质之间的关系及其对浮选行为的影响。硬质和软质高岭土表面Zeta电位随pH值的变化规律基本相同,具有相近的表面零电点（PZC）值。几种硬质高岭土的PZC值的变化范围为2．5－3．8。在较宽的pH值范围,软质高岭土比硬质高岭土的电位高。铝土矿中高岭石以硬质高岭石为主,结晶有序度低,与药剂作用不强,可浮性较软质高岭石差,在铝土矿反浮选中,需强化对高岭石的捕收作用。     

Aluminum-silicates flotation with quaternary ammonium salts

1　INTRODUCTIONThediasporic bauxiteinChinaisdifferentfromthegibbsite bauxiteandboehmite bauxiteinothercountriesbyitshighcontentofAl2 O3andSiO2 andlowmassratioofAl2 O3toSiO2 (massratioofAl2 O3toSiO2 =A/S ,usually5 6 ) .Theproductioncostofa luminumoxidefromsuchrefractorybauxiteby“sin tering”or“combining”technologiesismuchhigherthanthatbyBayer sprocess .Sothatthealuminum silicateganguessuchaspyrophyllite ,illiteandkaolin iteinthebauxiteisneededtoberemovedtoincreaseA/S .Hussainetal…     

Flotation evaluation and adsorption mechanism of medialan collector to wolframite

Medialan has preferable flotation performance to wolframite,under the conditions of the best flotation pH value 7.0 and low dosage,wolframite recovery is up to80%.Medialan shows poor flotation performance to quartz,but better to fluorite and calcite.However,fluorite and calcite are inhibited in a certain degree by adding medialan mixed with sodium silicate.Adsorption mechanism of medialan collector on wolfram surface was also studied by using infrared(IR)radiation spectrum,adsorption volume,and zeta potential.The results show that medialan can adsorb on wolfram surface in the form of chemistry adsorption,and as medialan collector dosage changes,change law of adsorption volume is similar with that of wolfram pure mineral flotation.Zeta potential results prove that zeta potential of wolfram surface moves negatively after adsorbing medialan collector.     

一水硬铝石型铝土矿铝硅浮选分离的溶液化学

分析了我国铝土矿中一水硬铝石和铝硅酸盐脉石矿物的晶体结构与表面性质,一水硬铝石与铝硅酸盐脉石矿物晶体结构的差异、表面断裂的Al-O和Si-O健及表面离子活性区的差别,可影响矿物表面的润滑性与可浮性,类质同象及各种晶格杂质离子也将影响浮选剂与矿物表面的相互作用和矿物可磨性,提出了正浮选、反浮吕硅分离的技术原型,用溶液化学与计算研究了其基本原理。结果表明,通过溶液化学计算可确定阴离子捕收剂正浮选脱硅时捕收剂,分散剂和PH三者之间的匹配关系,矿物的PZC与捕收剂的pKa值是阳离子捕收剂反浮选的主要控制参数,阴离子捕收剂反浮选时,铅盐和钙盐是浮选铝硅酸盐较理想的活化剂。     

羧甲基淀粉的取代度对其在反浮选中抑制一水硬铝石的影响(英文)

研究取代度不同的两种羧甲基淀粉(CMSL和CMSH分别表示取代度低和取代度高的羧甲基淀粉)在以十二胺(DDA)为捕收剂的阳离子反浮选中对一水硬铝石的抑制性能。考察了CMS的取代度对其抑制性能及作用方式的影响。单矿物浮选实验表明,在广泛pH值范围内,CMSL对一水硬铝石的抑制能力要好于CMSH。借助吸附量测试、动电位测量和原子力显微镜对CMS在一水硬铝石表面的吸附进行研究。结果表明:相对于CMSL,CMSH分子中具有更多的吸附点,因而在一水硬铝石表面具有较小的吸附量和较薄的吸附层厚度,并使一水硬铝石表面具有较强的电负性。溶液表面张力的测定和捕收剂DDA的吸附实验进一步揭示,CMSL分子的环式吸附构象可以罩盖更多的DDA从而显示优良的抑制性能,而CMSH/DDA体系则表现得更像一种表面活性剂。     

变性淀粉在铝硅矿物浮选分离中的作用机理

通过浮选实验、动电位和红外光谱测定,详细考察了变性淀粉在铝硅矿物浮选分离中的作用效果和机理。浮选实验显示：非离子淀粉和阴离子淀粉在pH＜6时,抑制一水硬铝石的浮选,但当pH＞6时,却对一水硬铝石浮选有活化作用;阳离子淀粉在较宽pH值范围内对一水硬铝石均有抑制作用;3种淀粉化合物在pH＜6时均活化高岭石的浮选,当pH＞6时活化作用较微。结果表明：变性淀粉是一水硬铝石型铝土矿反浮选中实现一水硬铝石和高岭石分离的有效调整剂,阴离子淀粉使矿物表面ζ电位更负,阳离子淀粉使矿物质表面ζ电位更正,非离子淀粉使矿物表面电位绝对值减小。由实验结果结合药剂与矿物作用前后的红外光谱分析,得出结论：非离子淀粉主要通过氢键作用吸附于矿物表面,而静电力和化学键合力在阴离子淀粉和阳离子淀粉吸附中发挥着重要作用。     

Flotation techniques for separation of diaspore from bauxite using Gemini collector and starch depressant

The floatability of diaspore and three kinds of silicate minerals,including kaolinite,illite and pyrophyllite,by a cationic Gemini surfactant as collector and starch as depressant was investigated as function of reagents concentration and pulp pH.Further studies of artificially mixed minerals and bauxite ore were also detailedly conducted.At last,the pre-desliming reverse flotation separation process was adopted.It can be concluded that the combinational use of a Gemini cationic collector and the starch dep...     

Mechanism and application on sulphidizing flotation of copper oxide with combined collectors

The effect of sodium butyl xanthate (NaBX) and dodecylamine (DDA) as combined collector on the sulphidizing flotation of copper oxide was investigated by flotation test, fluorescent pyrene probe, zeta potential, and infrared spectroscopy analyses. The micro-flotation results show that combined use of NaBX+DDA yields better effect than using NaBX at pH 7-11 only, and the optimal molar ratio of NaBX to DDA is 2: 1. The actual ores flotation shows that when the dosage of NaBX+DDA is (100+54) g/t, the copper concentrate grade and recovery are 15.93% and 76.73%, respectively. The fluorescent pyrene probe test demonstrates that the NaBX+DDA can reduce the micelle concentration in the pulp. The zeta potential and the infrared spectroscopy analyses indicate that chemical adsorption, hydrogen-bonding and electrostatic interaction can help to adsorb NaBX+DDA on the surface of malachite. Meantime, copper xanthate and copper-amine complexes may be generated during the adsorption process.     

Reverse flotation separation on diaspore and kaolinite in the presence of cationic polyacrylamide polymers

1　INTRODUCTIONChinaisrichindiasporebauxiteresources[1,2 ]whichpossessspecialpropertiessuchashighgradeofbothAl2 O3andSiO2 andlowFecontent,buttheAl/Si(massratioofAl2 O3toSiO2 )valueislow .Inordertotreatthediasporebauxite ,unitedmethodsandsin teringmethods[3] arestillappliedalthoughsufferingfromdisadvantagesincludingcomplextechnologyflowchart,highenergyconsumption ,highproduc tioncost ,andrestrainingfurtherdevelopmentofalu minaindustry .However ,byimprovingbauxiteAl/Si>10 ,wecanchoosem…     

Improvement of flotation behavior of Mengzi lead-silver-zinc ore by pulp potential control flotation

The electrochemical behavior of Mengzi lead-silver-zinc ore flotation system was studied. Based on the electrochemical characteristics of sulfide mineral flotation system, a stage potential control flotation was developed with the main parameters of pulp potential（φp）, pH value and collector dosage. Using N,N＇ diphenylamino-dithiolphosphoric acid（NNDDC） as a collector, which has good selectivity for galena flotation at pH 8.8 and pulp potential 330 mV, DDTC is used as secondary collector to improve both the grade and recovery of Pb and Ag. The pulp potential values significantly influence the floatability of practical minerals and single minerals when using NNDDC as the collector. The flotation recovery of galena reaches 85% at about 0.3 V and pH8.8. With the usage of pulp potential control during grinding and flotation, the new pulp electrochemical technology for Mengzi lead-silver-zinc ore flotation was developed. The results show that the grades of Pb and Ag of galena concentrate are 55% and 1 800 g/t, respectively, while the recoveries of Pb and Ag are 86.5% and 65%, respectively, the grade of Zn of marmatite concentrate is 42.5%, and the recovery of Zn is 91.25%.     

烷基羟肟酸对细粒锡石的浮选及其溶液化学性质(英文)

采用烷基羟肟酸作为捕收剂对细粒锡石进行浮选,并对其溶液化学性质进行研究。结果表明,3种烷基羟肟酸在碱性条件下对细粒锡石有较好的捕收能力,且适宜的浮选pH随着捕收剂碳链的加长而升高。金属离子对锡石浮选的影响主要由矿浆pH决定,金属离子浓度对锡石浮选也有影响。计算基团电负性得出烷基羟肟酸作为锡石捕收剂的适合烷基碳链长度大约为7。由溶液的组分浓度对数分布图(lgc—pH)分析可知,捕收剂以分子-离子共吸附模式作用于矿物表面。动电位测试及红外光谱分析表明,吸附反应中涉及到电荷作用力、氢键力和络合作用力,其最终产物可以表示为锡石的O,O-五元环结构的螯合物。     

捕收剂RL在铝土矿浮选中的应用

研究了一水硬铝石、高岭石及叶腊石等单矿物在RL为捕收剂时的浮选特性,考察了各种调整剂、难免离子对浮选体系的影响,在此基础上进行了人工混合矿和实际矿石的分离试验。实际矿石闭路试验结果表明：采用RL为捕收剂,碳酸钠和六偏磷酸钠为调整剂,精矿中Al2O3和SiO2的品位分别为70．74％和6．37％（精矿铝硅比为11．11）,Al2O3的回收率达到90．52％。     

Effects of sodium carbonate and calcium chloride on calcite depression in cationic flotation of pyrolusite

In the cationic flotation of pyrolusite using dodecyl ammine (DDA), the depressive effect of sodium carbonate and calcium chloride on the calcite mineral was investigated systematically through flotation experiments, FTIR analysis, contact angle measurements and zeta potential tests. The microflotation experiments showed that both depressant agents decrease the flotation recovery of calcite significantly. In addition, sodium carbonate acts as activator agent for pyrolusite, and increases its floatability. The flotation experiments and contact angle measurements indicated that the selective depression effect of sodium carbonate on the calcite mineral is more than that of calcium chloride. As evidenced by zeta potential and FT-IR analysis, sodium carbonate decreases the negative charges on the surface of calcite mineral and subsequently reduces the adsorption of DDA collector through electrostatic forces. At a pH of 7.5, using 2000 g/t DDA and 1500 g/t sodium carbonate, a pyrolusite concentrate containing almost 40% MnO with 71.5% recovery is achieved by carrying out the ore flotation experiments on the tabling pre-concentrate.     

直链烷基胺浮选铝硅矿物机理

研究了一水硬铝石和高岭石、叶蜡石及伊利石等几种含铝硅酸盐矿物在不同pH条件下的动电行为与浮选行为。一水硬铝石、高岭石、叶蜡石及伊利石的等电点（IEP）分别为pH6．2,4．3,2．0,3．4。在pH＞IEP时,烷基胺类阳离子捕收剂主要以静电作用吸附在一水硬铝石矿物表面,其浮选高岭石等3种铝硅酸盐矿物的可浮性大小顺序是叶蜡石＞高岭石＞伊利石。高岭石、叶蜡石和伊利石均是层状硅酸盐矿物,其破碎磨细时,将沿层间断裂,由于晶体结构的原因其层面荷负电荷。烷基胺类阳离子捕收剂以静电作用力吸附于铝硅酸盐矿物表面的层面使矿物疏水上浮。     

季铵型阳离子捕收剂在一水硬铝石和高岭石表面的吸附机理

研究十二烷基三甲基氯化铵（DTAC）和十六烷基三甲基氯化铵（CTAC）对一水硬铝石和高岭石的浮选行为。通过残余浓度法测定吸附等温线,荧光探针法和Zeta电位测试方法研究季铵型阳离子捕收剂在矿物表面的吸附机理。浮选结果表明：将DTAC和CTAC作为捕收剂,一水硬铝石的浮选回收率随着pH的增大而增加,而高岭石的浮选回收率随着pH的增大反而下降。当捕收剂的碳链增长时,矿物浮选回收率提高,但高岭石的增加幅度小于一水硬铝石的。在低浓度范围内,阳离子表面活性剂通过静电作用吸附在一水硬铝石表面,而对于高岭石,还存在离子交换作用。当浓度增大时,阳离子表面活性剂通过碳链间疏水缔合作用在两种矿物表面进一步吸附。矿物表面微极性研究表明：CTAC的疏水性比DTAC强,相同溶液浓度下CTAC在一水硬铝石表面能形成比在高岭石表面更大的胶团,这也说明阳离子表面活性剂碳链的增长对一水硬铝石吸附的影响要大,与浮选结果相吻合。     

Flotation Behavior and Mechanism of Anglesite with Salicyl Hydroxamic Acid as Collector

The flotation behavior of anglesite at different pulp pH levels was studied, with salicyl hydroxamic acid (SHA) acting as collector. The results demonstrated the effectiveness of SHA over a wide pH range. Zeta potential, adsorption, and x-ray photoelectron spectroscopy measurements were carried out to explore the interactions between SHA and anglesite. The results showed that the adsorption of SHA on the surface of anglesite was both chemical and physical. Furthermore, experiments with a bench-scale closed-flotation circuit proved that the collector can effectively recover anglesite from zinc-leaching residues (ZLRs). This work sheds new light on flotation of anglesite, providing a significant contribution to understanding of anglesite flotation and its application for disposal of ZLRs.     

Surface modification of ilmenite and its accompanied gangue minerals by thermal pretreatment: Application in flotation process

The effect of conventional thermal pretreatment on the surface properties of ilmenite and its accompanied gangue minerals was investigated using flotation experiments (microflotation and laboratory cell flotation), XRD, XPS and FT-IR analysis and zeta potential and contact angle measurements. After treatment at 600 °C for 25 min as optimal condition, the floatability of ilmenite is improved from 73.5% to 91% at a pH value of 6.3. As demonstrated by XRD and XPS analysis, under this pretreatment condition, the Fe³⁺ content increases by almost 16.5% without any phase decomposition and structural changes in ilmenite. FT-IR analysis and contact angle and zeta potential measurements give evidences that the improvement of ilmenite floatability can be related to the enhancement of collector adsorption and the formation of a more insoluble hydrophobic layer of ferric iron oleate. The ore flotation experiments show that the thermal pretreatment process without making a significant change in TiO₂ content of ilmenite concentrate enhances the TiO₂ recovery from 65.4% to 73.7%.